In recent years, the use of polymer packaging articles, particularly those made of thermoplastic polymers has been increasing year after year because of their excellent resistance to breakage, lightweight properties, and transparency as compared with conventional bottles made of glass, metals, or other materials. In particular, the conversion from conventional packaging articles to polymer packaging articles has progressed most rapidly in the beverage industry where plastic, or polymer, packaging articles are used in great quantity. Although not limited thereto, one of the most popular polymer compositions for use in polymer, or plastic, packaging articles is either polyethylene terephthalate (PET) or recycled polyethylene terephthalate (rPET).
In light of the above, great interest has recently arisen in the recycling of a wide range of plastic, or polymer, packaging articles. Given this, there is currently real interest in various solutions that would, if obtained, make the recycling of plastic packaging articles for more efficient and cost effective.
For example, much attention has been paid to the recycling of bottles or thermoform containers made of thermoplastic polymers, particularly PET, and even articles made of one or more polyester polymers. In general, PET bottles are fitted with various labels, for example, stretch labels made of polyolefins; heat-shrinkable labels made of polyesters, polystyrene, polyvinyl chloride, or other polymers; and tack labels made of polypropylene or other polymers. In recycling PET bottles, such bottles are usually collected from general consumers without removal of their labels, and then brought to, for example, recycling centers. These bottles are then washed, and their labels are removed by primary crushing, at which time, however, the crushed polymer materials may still include a portion of the labels, facestocks, or adhesive used to attach same in great quantity. Therefore, the conversion of PET bottles into recycled polymer pellets may require many intervening steps such as secondary crushing, specific gravity separation of labels in a liquid, dehydration and drying, specific gravity separation of labels by air blowing, and pelletization.